Integrated Noise Model (INM)

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The Integrated Noise Model (INM) is a computer model that evaluates aircraft noise impacts in the vicinity of airports. It is developed based on the algorithm and framework from SAE AIR 1845 standard, which used Noise-Power-Distance (NPD) data to estimate noise accounting for specific operation mode, thrust setting, and source-receiver geometry, acoustic directivity and other environmental factors. The INM can output either noise contours for an area or noise level at pre-selected locations. The noise output can be either exposure-based, maximum-level-based, or time-based.

What is INM Designed to Do?

In the United States, INM is preferred model typically used for FAR Part 150 noise compatibility planning and for FAA Order 1050 environmental assessments and environmental impact statements. The INM has many analytical uses, such as:

• Assessing current aircraft noise impacts around a given airport or heliport
• Assessing changes in noise impact resulting from new or extended runways or runway configurations
• Assessing changes in noise impact resulting from new traffic demand and fleet mix
• Evaluating noise impacts from new operational procedures
• Evaluating noise impacts from aircraft operations in and around National Parks

INM Version 7.0c

INM Version 7.0c is the most recent release of INM. It includes database updates and correction of minor software issues, but no new functionality added to INM Version 7.0b.

Database Updates and Changes

INM Version 7.0c includes approach noise data updates for many existing Airbus aircraft types, which are considered to better represent the approach noise generated near an airport and address a reference speed assumption issue in the INM Version 7.0b approach noise data for these aircraft. The affected aircraft types are the:

INM Version 7.0c includes an updated standard aircraft substitution list. 22 new aircraft are added to the substation list, 38 substitutions are modified, and 8 are deleted. The update is based on comprehensive review of aircraft configuration, aircraft aerodynamic performance, noise certification levels, and noise contour area comparisons.

INM Version 7.0c includes the addition of several new aircraft types to the INM system database, including five Cessna business jets, four Bell helicopter and two floatplanes, many of which used in air tour operations at national parks in the US. The new aircraft are the:

INM Version 7.0c also includes noise data updates for many existing aircraft types, many of which used in air tour operations at national parks in the US. The affected aircraft types are the:

• CNA182,
• CNA208,
• DO228,
• DO328,
• PA42,
• R44,
• and SC300C.

Minor corrections were also made to the data for several existing aircraft for INM Version 7.0c, details of which can be found within the INM 7.0c Release Notes.

Program Modifications and Corrections

• Several minor program modifications and bug fixes were made for INM Version 7.0c. These are described in detail in the INM Version 7.0c Release Notes (PDF).

Previous Versions of INM

INM Version 7.0c, released on January 3, 2012, is a free update to INM Version 7.0. You must already have INM Version 7.0, Version 7.0a or Version 7.0b installed to use this update. If you do not already have the previous version, you can order a complete software package using the INM 7.0c Order Form available below. The INM 7.0 User's Guide and Technical Manual are the current manuals for INM 7.0c.

The files below comprise the INM Version 7.0c update, installation instructions, and order form.

• INM 7.0c Update (EXE)
• INM 7.0c Release Notes (PDF)
• INM 7.0c Order Form (PDF)

User Guide and Technical Manual of INM Version 7.0

• INM Version 7.0 User Guide (PDF) (April 30, 2007)
• INM Version 7.0 Technical Manual (PDF) (January, 2008)

Release Notes of Previous Versions of INM

• INM Version 7.0b (PDF) (September 29, 2009)
• INM Version 7.0a (PDF) (September 17, 2008)
• INM Version 6.2a (PDF) (November 20, 2006)
• INM Version 6.2 (PDF) (May 19, 2006)
• INM Version 6.1 (PDF) (March 4, 2003)